Metal sound-record.



'l vi M0 5120:

T. H. MACDONALD. v

METAL SOUND RECORD.

APPLIUATION FILED MAY 14, 1910.

I 1, 07,1401 MMQM; 3 4

THOMAS H. MACDONALD, 0F BRIDGEPOR'I, CONNECTICUT, ASSIGNOR TO AMERICAN GRAPHOPHONE COMPANY, OF WEST VIRGINIA.

BRIDGEPORT, CONNECTICUT, A CORPORATION OF METAL SOUND-RECORD.

Specification of Letters Patent.

Patented Oct. 20, 1914.

Application filed May 14, 1910. Serial No. 561,311.

T0 aZZ whom it may concern lie it known that I, THOMAS H. Mao- DONALD, a citizen of the United States of America, and resident of Bridgeport, Connecticut, have invented .a new and useful Improvement in Metal Sound-Records, which invention is fully set forth in the following specification.

The object of this invention is to produce a sound-record of greatly improved durability without any sacrifice of quality.

It is well known that with the SOllIld-I'QC- ords now on the market each reproduction causes deterioration, and that after several hundred reproductions or sometimes even less the record becomes so poor as to be prac tically worthless. It has long been desired to obtain for permanent preservation records of celebrated personages, great singers, etc. Such records can be preserved for a long time, perhaps indefinitely; but each use thereof, for audible reproduction, to that extent tends to destroy them. By my invention I produce a permanent sound-record which can be used thousands of times without any appreciable deterioration, and which can be preserved for indefinite ages,

.yet without any sacrifice of quality.

My invention will be best understood by reference to the annexed drawings that illustrate preferred methods of procedure, the disks shown in the drawings being somewhat exaggerated in thickness for sake of clearness and the drawings themselves not being made to s 'alc but merely as illustrations.

In the drawings Figure 1 is an elevation intended to represent conventionally the production of an orig nal disk soundrecord of the vertically-undulating type, and

Fig. 1 is a similar view representing the production of an original disk soundrecord of the laterally-undulating type; Fig. 2 is an elevation in .licating the operation of rendering the surface of such original electro-conductive; Fig. 3 is a transverse vcrtical section through a conventional repre- .entation of an electro-plating bath for producing the clectroplate' masters or negatives ofthe originals, and Fig. 1 is a similar view representing the production from such negatives of electroplate positives Fig. 5 is a sectional view of a pair of rotating chucks, indicating the turning back of: the circular edge or rim of such metal positives; Fig. 6 isa vertical'secface of the revolving tablet 1. The recorder is arranged with itsdiaphragm practically horizontal, so that its stylus vibrates up and down to produce in the surface of tablet 1 a spiral record-groove having vertical undulations corresponding to sound-waves, a record-groove of the type disclosed in the Bell and Tainter Patent No. 341,214, May 1, 1886.

I Referring to Fig. l as a modification, the I slowly traveling recorder 35* has its diaphragm practically vertical, and its stylus vibrates laterally to produce in the tablet 1 a. record-groove having lateral undulations or zigzags corresponding to soundwaves, as described in the Jones Patent No. 688,739, December 10, 1901. The surface of the original record 1 (or 1"-) is then rendered electro-condu'ctive in any well-known manner, as by coating 'it carefully with finely powdered graphite, which may be brushed over the revolving tablet 1, by means of a brush 4, as indicated in Fig. 2. Thereafter, a metallic reverse or negative 5 is obtained from the original, by electroplating in the well-known manner.

Fig. 3 represents conventionally a plating-bath 6 containing a number of originals 1 having an GlOCtl'OdQPOSltGCl coating or metal plate 5 adhering to each. These electroplatcs 5 are separated from the originals, and present a reverse of the original soundrecord; and this reverse-surfaceis preferably cleaned, nickel-plated (if of copper), and polished. From these reverse electroplates 5, positive metallic records are then obtained. in any well-known manner, as by repeating the electroplating, which is illustrated by Fig. 4:, which shows an ordinary plating-bath 6 containing a number of the metallic negatives 5 upon which the metallic positives 7 are being deposited by electrolysis in the well-known manner. These positives 7 are separated from the negatives 5, and present exact copies of the original records produced in the tablet 1. These positive metal copies 7 will be preferably cleaned, nickel-plated (if of copper) and polished or buffed, to constitute the metallic record-surfaces of the finished article.

' The object of the steps described in the preceding paragraph is to obtain metallic soundr.ecords capable of audible reproduction upon the talking-machine. Although I have describedthe particular steps of first recording in a wax-like material and subsequently obtaining therefrom electroplates or eorflparatively thin. sheets of, metal The edg 'nf'f'each recor'dds'noW turned back- 'wardn-ndinwardfas ndicated by Fig. 5, in

which 8- .-8fjzis indicated Fig. 5 of the .35

"drawings represent two revolving circular heads'or chucks, a little smaller in diameter than.the metal disk 'Z. Each of the disks 7 in turn centered between the two chucks,

- as by means of a stud 9 projecting from the so center of one chuck and passing through a center hole in the disk 7 into a correspond seat into the other chuck. 10 indicates aftool pressed against the protruding edge 11 off. the revolving metal disk 7, which is thereby bent as indicated. Assuming that 'therec rd-groove is on the right hand of the disk7, as up caring in Fig. 5, then the edgell is flanged backward (to the left) in Fig. 5. And thereafter the extreme edge of this rim 11 is bent inward to produce a slight. lip which may be accomplished by further use of a tool against the revolving edge ofthe rim. In cross-section this back ward and inward bending of riin 11 would appear as a slight hook. See Fig. 6. Re ferring to Fig. 6, two of such metal records 7, preferably of different selections, are placed back to back, with their inturned 'rims llf-jll toward each other; and between the twois placed a lump or mass 12 of suitable material, preferably the thermoplastic material or stock (earthy matter blended with shellac or other gum as a binder) employed. in making ordinary disk records. The whole is then inserted be tween the gaws 13l3 of a suitable press. being preferably fitted in circular dies provided with circular depressions or seats; and the press is operated to compress the two metal disks together and squeeze the material 12. The pressure of the jaws 1313 causes the. thermo-plastic mass 12 to spread radially outward, until it abuts against the rims of the metal shells and their inturned lips; and thereupon the rims are forced outward by the oncoming material 12, until they assume the full. cylindrical outline of the confining walls of the dies, by which time the rims 11'11 will have come together. More or less of the extreme inturned lip at the very edge of the I rims will still remain for looking into the interposed material 12, which bythis time will have resumed its normal hardness. The article so produced, shown in edge view by Fig.7 and in face view by Fig. 8, appears to be a disk of metal; each face is of metal and the cylindrical edge is likewise of metal. The joint between the two rims 11-11 appears as an arrow (black) line 14. If desired the two record-surfaces of the finished article may be again cleaned and buffed, and the article is now ready for use.

My invention is not limited to the par ticular methods of forming metallic records shown and described, the limits of the invention being defined in the annexed claims. Having thus described my invention, I claim:

1. As an article of manufacture, a doublefaced disk sound-record consisting of two metallic-surfaces each provided at its rear with an inturned lip, and a connecting layer of material that will spread under pressure uniting said lips.

'2. A two part sound-record consisting of two metal shells each containing a soundrecord on its face and an inturned lip at its rear, and non-metallic material that will spread under pressure uniting said lips.

IOU

A double-faced. sound-record consisting of two metallic shells each having a sound-record on its face and having an inturned lip at its rear, and an interposed material that will spread under pressure engaging said lips and locking said shells together.

In testimony whereof I have signed this specification in the presence of two subscribing witnesses.

'lTllOMAS l-l. MACDONALD.

Witnesses A. 15. Kuoueu, C. W. Hui-mane. 

